In devices (for example, a large-scale telescope for astronomical observation, a large-scale parabolic antenna for satellite communication, a large-scale overhead travelling crane, or automatic processing machine) having a large-scale structure that includes a power consumer that consumes electric power (for example, a driver or a sensor), the devices being driven largely around a rotation axis by a driver, conventionally, in order to minimize an occurrence of noise and to improve the easiness of maintenance, thick power cables are laid across a long distance. In addition, in the case of a device requiring drive precision, a cable winding device with a complex mechanism is additionally provided so as not to apply the tension of the cable to a driving device.
In contrast, Patent Literature 1 discloses, as an example of supplying electric power through a wireless power supply that employs a radio wave scheme, an antenna mirror surface adjusting device in which an electromagnetic wave is externally transmitted to an actuator that adjusts the mirror surface shape of an antenna reflector loaded in a space flying object such as an artificial satellite. According to this technology, a transmitter that transmits an electromagnetic wave, a power converter that converts the electromagnetic wave into electric power, actuators that adjust the mirror surface shape, and a controller that controls the actuators are provided, and the mirror surface shape of the antenna reflector is adjusted using wirelessly transmitted electric power with electromagnetic waves as source electric power.
In addition, Patent Literature 2 discloses an energy transmission system that wirelessly transmits energy to an electrical power receiver of a vehicle from an electrical power transmitter provided in a roadside device. According to this technology, the roadside device including a transmission device that transmits transmission condition information determining a transmitting direction of an electromagnetic wave to a vehicle is provided, and the vehicle is provided with a signal transmitter that receives the transmitted transmission condition information and transmits, to a signal receiver of the roadside device, correction information to correct the transmitting direction of the electromagnetic wave based on the transmission condition information. Hence, the precision of the transmitting direction of the electromagnetic wave is improved.